Showing posts with label answer. Show all posts
Showing posts with label answer. Show all posts

Friday, 17 June 2011

polling in 8085 microprocessor

What do you mean by polling in 8085.

When the microprocessor receives an Interrupt Service Request (ISR) on the interrupt line it must determine which of the devices connected to that input sent the request.

Software Polling is one method by which it can do so.

In Software Polling:

A software routine is used to identify the device requesting service. It does so by checking each device to see if it was the one needing service.

Tuesday, 22 March 2011

Jump Command

If the program counter is always one count ahead of the memory locations from which the machine code is being fetched, how does the microprocessor change the sequence of program execution with a "Jump" execution?

During a jump instruction, the program counter is loaded with a new address that is not necessarily the address of the next sequential instruction. After a jump, the program execution continues from the new location in memory.

Friday, 4 February 2011

Physics Practice MCQs

1-The relation (B. L)I=UI is called
a-Amperes law b-Ohm’s law
c-Gauss’s law d-Newton’s law

2-(B. L)i is equal to
a-UI b=UNI
c-UNI/2r d-U/I

3-The magnetic field of induction of Toroid is
a-UNI/2r b-UI/2r
c-U2r/NI d-2r/UI

4-The magnetic field of induction of solenoid is
a-Uin b-UI
c-Uin/2r d-2r/UnI

5- is a coil of an insulated copper wire
wound on a long cylinder.
a-solenoid b-Toroid
c-Battery cell d-Hollow cylinder

6- is a coil of an insulated copper wire
wound on a circular shape material.
a-Toroid b-Solenoid
c-Circuit d-Potentiometer

7-The dot product between tangential components
And the summation of all the components of length
is equal to product of and
a-U and I b-U and N
c-U and V d-U and R

8- (B. L)=UI here U is called
a-Permeability of free space
b-Permitivity of free space
c-Relative permitivity
d-Di-electric constant

9-The value of U is
a-4*10^-7weber/A.m b-4*106-7weber/A.m
c-4*10^-7weber/C.m d-4*10^7coulomb/weber.m

10-The unit of B is
a-Weber b-Coulomb
c-Ampere d-Ohm

11-Acording to Biot and Savart law the magnetic field
of induction is directly related with
a-Twice of the current.
b-Twice of the voltage.
c-Twice of the resistance.
d-Thrice of the voltage.

12-What does the relation B2I/r represents.
a-Biot and Savart law b-Faraday law
c-Lenz law d-Inverse square law

13-Acording to Biot and Savart law the magnetic field
of induction B is related to
a-1/r b-r
c-r^2 d-i/r^2

14-Acording to Biot and Savart law the equation
B=(constant)2I/r here constant is
a-U/4 b-4U/
c-U/4r d-4r/U

15- l=Circumference of a circle which is equal to
a-2r b-2r^2
c-r^2 d-4/3 r^3

16-The magnetic field of induction will be maximum
If
a-B and L are in same direction.
b-B and L are in opposite direction.
c-B and L are perpendicular.
d-B is zero

17-Ampere’s law was proposed by
a-Ampere b-Faraday
c-Newton d-Coulomb

18-Ampere’s law carries which variable quantity.
a-I b-V
c-R d-C

19-The magnetic field of induction will be minimum if
a-B and L are in same direction.
b-B and L are in opposite direction.
c-B and L are perpendicular.
d-B is zero

20-Magnetic flux are the lines of forces around a
a-charge b-magnet
c-electron d-positron